Apparatus and method for preventing unwanted opening of a locked enclosure
AssigneeLockmasters Security Institute, Inc.
InventorThomas E. Jasper
Life of this patent
Estimating the term…
Abstract
An apparatus for preventing unwanted opening of a locked enclosure. The enclosure includes a lock, a door and a door bolt. The door is openable when the door bolt is retracted from a structure surrounding the enclosure. The apparatus includes a frangible guard plate, and an arm coupled to the guard plate by a spring. The arm is maintained in a first position under a bias of the spring. When the guard plate is fractured, the arm is free to move from the first position into a second position. The arm is positioned to engage the door bolt in the second position, thereby preventing retraction of the door bolt.
Claims9
An apparatus for preventing unwanted opening of a locked enclosure including a lock mechanism, comprising:
- an arm having first and second ends and rotatably mounted at a point between the first and second ends so as to be rotatable in a first direction between a first position and a second position;
- a first spring operatively coupled to and rotatably biasing the first end in a second direction which is rotationally opposite to the first direction;
- a second spring operatively coupled to and rotatably biasing the second end in the first direction;
- and
- a frangible guard plate coupled to the first end of the arm by the first spring, thereby preventing rotation of the second end of the arm in the second direction by the second spring so as to maintain the arm in the first position, wherein when the frangible guard plate is fractured, the arm is free to move from the first position to the second position due, at least in part, to the bias of the second spring on the second end of the arm such that when the arm is in the second position, the second end of the arm is positioned to engage with a portion of the lock mechanism, thereby preventing the unwanted opening of the locked.
A method of preventing unwanted opening of a locked enclosure including a lock, comprising:
- rotatably mounting an arm to a housing at a point between first and second ends of the arm;
- coupling the first end of the arm to a frangible guard plate with a first spring;
- maintaining the arm in a first position relative to the frangible guard plate with the arm under a first bias of the first spring;
- freeing the arm for rotation from the first position when the frangible guard plate is fractured such that the connection of the first end of the arm to the frangible guard plate by the first spring is released;
- and
- rotating the arm into a second position in engagement with a member of the lock, thereby preventing the unwanted opening of the locked enclosure.
Dependencies are inferred from the claim text.